A multivitamin and mineral supplement boosted the birth weight of children born to undernourished women, says a trial from India, results that could have lifelong implications for the offspring.
The results, while obviously important for the developing world, may also have implications for developed countries where low income mothers are often deficient in a number of micronutrients (vitamins and minerals), including vitamins C and E, vitamin B complex and folate.
“Low birth weight (LBW) (less than 2500g) is a major predictor of neonatal and infant mortality,” explained lead author Piyush Gupta from the University College of Medical Sciences, Delhi.
“Infants who are small or disproportionate in size at birth also have an increased risk of developing coronary heart disease, type 2 diabetes mellitus, stroke, and hypertension during adult life. It is postulated that these diseases are programmed by inadequate supply of nutrients to the developing foetuses,” said Gupta.
The research study
Writing in the new issue of the Archives of Pediatrics & Adolescent Medicine, Gupta and colleagues report the results of a randomised trial involving 200 women who were 24 to 32 weeks pregnant and either underweight (having a body mass index of less than 18,5) or with a low haemoglobin level (between 7 and 9g per decilitre), which are markers of malnourishment.
The researchers assigned 101 women to the placebo group (containing only calcium), and the other 99 received a tablet containing 29 micronutrients, including all of the 15 micronutrients recommended by the World Health Organisation (WHO) and the United Nations Children's Fund for supplementation in pregnancy. Both groups were instructed to take the tablets daily. Supplements of iron and folic acid were given to both groups.
After birth, 170 of the newborns were followed for seven days to detect any evidence of congenital abnormalities or other conditions or illnesses.
Gupta and colleagues report that women in the micronutrient group gained an average of 9,2kg during their pregnancies, compared with 8,7kg in the placebo group.
After adjusting the data for other factors that affect birth weight, the researchers report that babies of mothers from the micronutrient group weighed an average of 98g more and were 0,8cm longer.
Low birth weight was recorded in only 15,2 percent of the babies from mothers in the micronutrient supplement group, compared to 43,1 percent in the placebo group.
Lower neonatal illnesses
“We concluded that multi-micronutrient supplementation targeted at pregnant undernourished women may decrease the incidence of LBW infants, despite no statistically significant change in birth weight. This translated into significantly lower neonatal illnesses during the first week of life in the micronutrient group,” wrote the researchers.
They also note that the potential benefits of the multivitamin and mineral (MVM) supplements may be underestimated in this trial because, for ethical reasons, the study compared the MVM to iron and folic acid supplementation, and not to no supplementation.
"Our findings are of a preliminary nature and need to be further corroborated," wrote Gupta. "We advocate community-based trials in deprived populations to ascertain the impact of a supplementation schedule lasting throughout pregnancy. The sample size should be large enough to evaluate the effect of such supplementation on neonatal morbidity and mortality, in addition to the size at birth."
Towards cost-effective interventions
In an accompanying editorial, Rachel Haws and Gary Darmstadt from Johns Hopkins University, Baltimore said: "Neonatal deaths are traditionally viewed by child survival programmes as relatively difficult to prevent, but new studies are strengthening the limited evidence base for highly cost-effective interventions that can save newborn lives in developing countries.
"As researchers build the evidence base for cost-effective interventions, policy makers, researchers and programme managers must collaborate with donors, governments and non-governmental organisations to invest fully and long-term in integrated maternal, newborn and child health strategies," they said.
The multivitamin and mineral supplement consisted of: beta carotene (2500IU), vitamin B1 (1mg), riboflavin (1,5mg), vitamin B6 (1mg), vitamin B12 (1mcg), vitamin C (50mg), vitamin D3 (200IU), tocopherol acetate (7,5mg), calcium pantothenate (5mg), folic acid (0,15mg), niacin (niacinamide 20mg), vitamin B3 (30mcg), zinc (15mg), potassium iodide (0,15mg), iron (ferrous fumarate, 10mg), magnesium oxide (100mg), manganese sulfate (2,5mg); copper (2mg), calcium (162mg), phosphorus (125mg), potassium (40mg) chloride (36,3mg), chromium (25mcg), molybdenum (25mcg), sodium selenate (30mcg), nickel (5mcg), silicon dioxide (2mg), vanadium (10mcg), and boron (150mcg). - (Decision News Media, January 2007)
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